1. Field of the Invention
This invention relates to pipeline inspection tools, and more particularly to apparatus and methods for data collection and analysis for an in-line inspection tool.
2. Background of the Invention
Oil, petroleum products, natural gas, hazardous liquids, and the like are often transported using pipelines. The majority of these pipelines are constructed from steel pipe. Once installed, a pipeline will inevitably corrode or otherwise degrade. Proper pipeline management requires identification, monitoring, and repair of defects and vulnerabilities of the pipeline. For example, information collected about the condition of a pipeline may be used to determine safe operating pressures, facilitate repair, schedule replacement, and the like.
Typical defects of a pipeline may include corrosion, gouges, dents, and the like. Corrosion may cause pitting or general wall loss, thereby lowering the maximum operating pressure of the pipeline. Vulnerabilities may also include curvature and bending anomalies and combined stress and chemical or biological action such as stress corrosion cracking. Without detection and preemptive action, all such defects and vulnerabilities may lead to pipeline failure.
Information on the condition of a pipeline is often collected using an in-line inspection tool. Ferromagnetic pipelines can be inspected for defects including cracks along the axis of a pipe by a limited number of technologies. These technologies include magnetic flux leakage (MFL), ultrasonic inspection (UT), eddy current inspection, and, in certain limited applications, electromagnetic acoustic transducers (EMAT).
Many in-line inspection tools use a pulsed signal source and sensors to collect information about a pipeline as they travel therethrough. In the past, in-line inspection tools have used technologies such as ultrasonic transducer (UT) inspection, eddy current inspection, electromagnetic acoustic transducer (EMAT) inspection and other technologies involving a transmitted and received energy pulse. Such technologies have been limited by low relative signal strength and low signal to noise ratio, further compromised by the noisy background of the pipeline environment.
While some technologies are more adversely affected by these factors than other are, all such techniques can be improved with better signal detection and recognition. What is needed is a better device and method for the generation and reception of pulsed signals for the various inspection technologies.